PHOTOS: The 2015 Sydney to Hobart yacht race

Super-maxi Comanche takes the lead in the 2015 Sydney to Hobart. Photo by Cameron Spencer/Getty Images.

American supermaxi Comanche, owned by Netscape billionaire Jim Clark, whose Australian wife Kristy Hinze-Clark is on board, has opened up an early lead against key rival Wild Oats XI in the 71st Sydney to Hobart yacht race.

By 4pm, three hours after the race start, Comanche had lready opened up 1.6 nautical mile lead over fellow US supermaxi Rambler with Wild Oats 2.3 nautical miles behind as the boats fly down the coast on a northeasterly breeze before they hit a southerly headwinds at 30-35 knots tonight.

While 108 boats started the race, four have already retired, including the first all-Chinese entrant, Ark323, following a collision shortly after the start, along with Cougar II, one of two Tasmanian entries, with a whole punched in the rear of the boat, UK entry Lupa of London and M3, which has a broken forestay.

Even the start boat got into trouble and began taking on water, forcing it to miss the race. A horn replaced to traditional canon to indicate the start.

While eight-time line honours winner Wild Oats XI, an eight-time had a good start, she was soon caught by Sydney accountant Anthony Bell’s Perpetual Loyal in the race up the harbour, before Comanche jumped in front and powered ahead as the boats started to run with the wind, heading south at speeds in excess of 20 knots.

Despite the dangers of gale force winds overnight, the lead boats are expected to be entering Bass Strait around 2am tonight, with the potential for the lead boats to cross the finish line late on Sunday night.

Here are some photos of the start of the race.

Comanche, Wild Oats XI and Perpetual Loyal dice for the lad on the way out of Sydney Harbour.

Photo by Cameron Spencer/Getty Images

Co-owner Kristy Hinze-Clark, who's sailing in her first Hobart, and Australian Olympian James Spithill on Comanche

Photo by Cameron Spencer/Getty Images

US boat Comanche is chased down the coast by Sydney's celebrity-packed supermaxi Perpetual Loyal.

Comanche is expected to be the fastest boat in the fleet and is a downwind flyer, having set the monohull speed record last year.

Photo by Cameron Spencer/Getty Images

100ft US supermaxi Rambler, owned by George David, former United Technologies Corporation chairman and CEO.

Photo by Cameron Spencer/Getty Images

The bowmen on 70ft Queensland entry Black Jack, named in honour of F1 champion Sir Jack Brabham, gets ready to set the gennaker.

Photo by Cameron Spencer/Getty Images

Discoverer of Hornet among the rest of the fleet in the race out of Sydney Heads. The 72ft boat is crewed by members of UK Armed Forces.

Photo by Cameron Spencer/Getty Images

Debut Italian entry Maserati, a Volvo 70.

Photo by Brendon Thorne/Getty Images.

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